Catherine M. Tangen
Dr.P.H., University of North Carolina at Chapel Hill, Biostatistics, 1997.
M.S., University of North Carolina at Chapel Hill, Biostatistics, 1990.
B.S., University of Washington, Zoology, 1985.
Dr. Tangen's research interests include the design and analysis of clinical trials and non-parametric covariance adjustment, particularly for survival data. She is the statistician for Phase II, Phase III and ancillary studies for genitourinary cancers (e.g., prostate, bladder, renal, testes) in the Southwest Oncology Group. In addition to therapeutic trials, she is also the primary statistical investigator for the Prostate Cancer Prevention Trial (PCPT). The PCPT is a large (18,800 men), randomized, double-blind trial whose primary objective is to test the difference in biopsy-proven period prevalence of carcinoma of the prostate between a group of participants treated with finasteride and a group treated with placebo for seven years. The primary results, which were reported in June 2003, showed a 25% reduction in the period-prevalence of prostate cancer among those on finasteride relative to placebo. However, there was also a small but statistically significant increase in the rate of high grade cancer on the finasteride arm. A subsequent paper related to the prevalence of prostate cancer in men with normal PSA levels was published in the summer of 2004. A number of other manuscripts addressing the high grade issue and other topics are planned or currently underway.
The “Biology of PCPT” program project (P01) was submitted in October 2003 and resubmitted in June 2004. This P01 provides each project access to the invaluable repository of PCPT biospecimens and data. Each project is closely linked by interactive specific aims and planned collaborations. The five projects deal with (1) androgen metabolism, (2) diet and diet-related factors, (3) insulin-like growth factor axis and insulin resistance, (4) genotypic and phenotypic studies of inflammation, and (5) oxidative damage and DNA repair. These projects will use a nested case (n=1800) –control (n=1800) design to develop the P01 theme which is the genetic, metabolic and environmental factors associated with the risk of prostate cancer overall or high-grade disease and the effects of these factors on finasteride preventive efficacy. The mechanisms underlying these risk-factor associations also will be assessed. There will also be three cores which provide services: administrative, pathology and genotyping, and biostatistics. Dr. Tangen will serve the role as Core Director of Biostatistics for this program project.
The results of Dr. Tangen’s statistical research methods provide non-parametric treatment parameter estimates which clarify the components of bias adjustment and variance reduction. There are no formal assumptions required for how a response variable is related to the covariables. The rationale for non-parametric covariance analysis is based on the randomization in the study design. Computations for these methods are through the application of weighted least squares to fit linear models to the differences between treatment groups for the means of the response variable and the covariables jointly with a specification that has null values for the differences in covariates. Dr. Tangen is currently working on applying her non-parametric covariance methods to a survival function to describe the prevalence of a transient condition. Non-parametric extensions to the work of Pepe, Longton, and Thornquist are being explored.
Insulin-like growth factors and insulin-like growth factor-binding proteins and prostate cancer risk: results from the prostate cancer prevention trial.. Cancer prevention research (Philadelphia, Pa.). 6(2):91-9.. 2013.
Plasma Phospholipid Fatty Acids and Prostate Cancer Risk in the SELECT Trial.. Journal of the National Cancer Institute. 105(15):1132-1141.. 2013.
Long-term survival of participants in the prostate cancer prevention trial.. The New England journal of medicine. 369(7):603-10.. 2013.
Intermittent versus continuous androgen deprivation in prostate cancer.. The New England journal of medicine. 368(14):1314-25.. 2013.
Associations of Serum Sex Steroid Hormone and 5α-Androstane-3α,17β-Diol Glucuronide Concentrations with Prostate Cancer Risk Among Men Treated with Finasteride.. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology.. 2012.
Moving a randomized clinical trial into an observational cohort.. Clinical trials (London, England).. 2012.
Improved Overall Survival Trends of Men with Newly Diagnosed M1 Prostate Cancer: A SWOG Phase III Trial Experience (S8494, S8894 and S9346).. The Journal of urology. 188(4):1164-9.. 2012.
Evaluation of Vitamin E and Selenium Supplementation for the Prevention of Bladder Cancer in SWOG Coordinated SELECT.. The Journal of urology. 187(6):2005-10.. 2012.
Prostate cancer--uncertainty and a way forward.. The New England journal of medicine. 367(3):270-1.. 2012.
Indications for and use of nonsteroidal antiinflammatory drugs and the risk of incident, symptomatic benign prostatic hyperplasia: results from the prostate cancer prevention trial.. American journal of epidemiology. 176(2):156-63.. 2012.
Vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT).. JAMA : the journal of the American Medical Association. 306(14):1549-56.. 2011.
Phase III Trial of Selenium to Prevent Prostate Cancer in Men with High-grade Prostatic Intraepithelial Neoplasia: SWOG S9917.. Cancer prevention research (Philadelphia, Pa.). 4(11):1761-9.. 2011.
An empirical evaluation of guidelines on prostate-specific antigen velocity in prostate cancer detection.. Journal of the National Cancer Institute. 103(6):462-9.. 2011.
Association of symptomatic benign prostatic hyperplasia and prostate cancer: results from the prostate cancer prevention trial.. American journal of epidemiology. 173(12):1419-28.. 2011.
Repeat polymorphisms in estrogen metabolism genes and prostate cancer risk: results from the Prostate Cancer Prevention Trial.. Carcinogenesis. 32(10):1500-1506.. 2011.
Serum estrogen levels and prostate cancer risk in the prostate cancer prevention trial: a nested case-control study.. Cancer causes & control : CCC. 22(8):1121-31.. 2011.
Estimating Covariate-Adjusted Log Hazard Ratios for Multiple Time Intervals in Clinical Trials Using Nonparametric Randomization Based ANCOVA. Statistics in Biopharmaceutical Research. 3(2):232-241.. 2011.
Biomarkers of systemic inflammation and risk of incident, symptomatic benign prostatic hyperplasia: results from the prostate cancer prevention trial.. American journal of epidemiology. 171(5):571-82.. 2010.
Androgen receptor CAG repeat length and association with prostate cancer risk: results from the prostate cancer prevention trial.. The Journal of urology. 184(6):2297-302.. 2010.